318 Heads: bad valve job?

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Alex "Berkowitz"

76 brazilian hardtop
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Hi guys.

I´ve just picked my heads back from the machine shop, went checking it and found some "odd" stuff.

First: putting a straight edge on the top of the stems, all exaust valve tips are higher than intakes. The difference is around 0,039".

As I got the heads assembled, I measured the instaled valve height from the TOP of the retainers to the spring seats.

On one of the heads, 6 valves were at 1,7716", 1 at 1,7815" and 1 at 1,8012".
On the other head, there were also 6 at 1,7716", one at 1,7618" and one at 1,7815".

The difference at the retainers seems to be small, but at the tips, a bit too high.

Oh, I'm running Edelbrocks 5877 springs, wich should have a installed height of 1,65".
I don't believe the retainers are 0,12" thick, are they?


This is the first time I'm assembling an engine, and I don't really know what I should check next.

So, should ALL the valve stem tips be at the same height?
If they should, considering the mentioned heights at the retainers, what would be the right move?
Grinding the tips?

And about the valve height?
Is it ok, or should I run shims?

Just to mention, the cam is a SUM-K6901, 218°/228° @0.050", and .441" lift both intake and exaust.

Thanks!

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I would not accept them.
 
Alex,

You should be checking the Valve Spring Height,

From the Valve Spring Seat {Top of the Shims} to the underside {bottom}
of the Valve Spring Retainer or the 'Outside Edge' of the Valve Spring.

Not, to the top of the Valve Spring Retainer.



ValveSpringDetail.gif
 
The valve stem height on a Mopar is critical. Not just the spring height.
 
Rod,

One Step at a Time.

I believe this is the 'first time' Alex is putting together an Engine.

It is not 'uncommon' for the Exhaust Valve to be taller in the Cylinder Head
than the Intake Valve, as the Exhaust Valve is usually .020" longer than the Intake Valve.

Chrysler allows for a .030" variance in installed set height between the Intake and Exhaust Valves
at the top of the Stems.

Though I like to keep it closer, there should be no problem in operation.

The SUM-K6901 Camshaft {.441"/.441" Lift ~ 276*/288* Duration} and Hydraulic Lifters will be
fine up to a .030" difference.
 
Step

1.....grind seats which moves the valve stems up higher as the seat "sinks."

2----face the stems down to proper installed height

3---valve retainers will ALSO now install "too high," so install shims below springs to shim them to proper height.

As Rob says, Mopar valve height is especially critical because factory rockers are not adjustable.
 
69 Cuda 440 said:
Rod,

One Step at a Time.

I believe this is the 'first time' Alex is putting together an Engine.

It is not 'uncommon' for the Exhaust Valve to be taller in the Cylinder Head
than the Intake Valve, as the Exhaust Valve is usually .020" longer than the Intake Valve.

Chrysler allows for a .030" variance in installed set height between the Intake and Exhaust Valves
at the top of the Stems.

Though I like to keep it closer, there should be no problem in operation.

The SUM-K6901 Camshaft {.441"/.441" Lift ~ 276*/288* Duration} and Hydraulic Lifters will be
fine up to a .030" difference.
Click to expand...

Agreed completely. Let hope he's within those tolerances.
 
This is one area I always laugh at chebbie guys about. They don't care much about stem height because they have adjustable rockers. lol They don't get the importance of proper valve train geometry at all.
 
Along with worrying about the valve job, don't forget that milled heads and or deck will affect effective valve lash, too.
 
67Dart273 said:
Along with worrying about the valve job, don't forget that milled heads and or deck will affect effective valve lash, too.
Click to expand...

67 Dart 273,

Easy, I think you're scaring him now.

Maybe we should find out all the Machine Work that was performed.
 
69 Cuda 440 said:
67 Dart 273,

Easy, I think you're scaring him now.

Maybe we should find out all the Machine Work that was performed.
Click to expand...

True. Still though, it's nothing that cannot be fixed and relatively easily....by a competent machine shop. IF it needs fixing.
 
69 440,that's great info. I would be very curious, what the actual 45 angle sits. "Sunk,ugh
." The Serdi's are sweet,done right. The old school Sioux,takes WAY more time.But you can put the valve angle,where you want it.(Runout gauge,.001 on the runout?....)
 
I always preferred the old Sioux stone myself. I've used the Serdi too. I learned a Sioux wet setup. I guess I just like what I learned on. IMO though, as long as you keep the stones dressed properly, you can equal the Serdi if you take your time. I am sure there will be those who will argue.
 
Rob,more than agree. Definitely, something to be handled, by someone old school. F.W.I.W,My guy tried the cheapo stones,on GM LS heads. The stones disappeared, so quickly. (Lol).
 
I also would not accept those heads as delivered for the various reasons noted.
 
Abodybomber said:
Rob,more than agree. Definitely, something to be handled, by someone old school. F.W.I.W,My guy tried the cheapo stones,on GM LS heads. The stones disappeared, so quickly. (Lol).
Click to expand...

Probably HF stones. LOL
 
The Valves do 'appear' to be sitting properly.

They sure do not look 'sunken'. And they look like 'new' units.

I use a 'Sunnen' VGS-20 Valve/Guide Seat Machine with a 3-Angle Cutter,
to provide for 'equal cut 'Valve Seats.

Then touch the 45* Valve Seat with a Kwik-Way Grinder, with a Medium-Grit
Stone {Street/Strip Applications}.

The 'Top-of-the-Line' Valve Seat Machine for Performance Work is by far the 'SERDI'.
 
69 Cuda 440 said:
The Valves do 'appear' to be sitting properly.

They sure do not look 'sunken'. And they look like 'new' units.

I use a 'Sunnen' VGS-20 Valve/Guide Seat Machine with a 3-Angle Cutter,
to provide for 'equal cut 'Valve Seats.

Then touch the 45* Valve Seat with a Kwik-Way Grinder, with a Medium-Grit
Stone {Street/Strip Applications}.

The 'Top-of-the-Line' Valve Seat Machine for Performance Work is by far the 'SERDI'.
Click to expand...

No argument here. But how many races have been won and records set with good old Sioux grinding rocks? Certainly not saying they are better, but surely you cannot discount something that has stood the test of time for 100 years.
 
I'd set them up level and add kerosene or a light oil to a couple of chambers. Then look in from the ports to see if the valves are sealing, since we are on the topic of seats... Or pull a couple of valves and lap them to see if they are sealing and check were the seat is on the valve face.
 
Rod,

The 'old school' Valve Grinding is still a favorite of many Racers.

* Sioux
* Kwik-Way
* K.O. Lee
* Hall-Toledo
* Winona

Even Sox & Martin were using an old 'Black & Decker' Valve Grinding Kit
up through 1968.
 
69 Cuda 440 said:
Rod,

The 'old school' Valve Grinding is still a favorite of many Racers.

* Sioux
* Kwik-Way
* K.O. Lee
* Hall-Toledo
* Winona

Even Sox & Martin were using an old 'Black & Decker' Valve Grinding Kit
up through 1968.
Click to expand...

Yes, cause it's CHEAP. LOL
 
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